Aoyagi S, Hiney K M, Baker D H
Department of Animal Sciences, University of Illinois, Urbana 61801, USA.
J Anim Sci. 1995 Mar;73(3):799-804. doi: 10.2527/1995.733799x.
Three chick experiments were conducted to investigate possible explanations for why pork liver provides no bioavailable Cu to chicks. Autoclaving, acid-hydrolysis, and protease-digestion increased (P < .01) Cu bioavailability in pork liver to 32, 46, and 63%, respectively, from virtually 0% of the Cu in unprocessed pork liver (relative to CuSO4, which was set at 100%). Addition of EDTA at 200 mg/kg to the diet containing 1 mg of Cu/kg from unprocessed pork liver also resulted in an increased (P < .07) Cu bioavailability, to 23%. Tissues representing different sources of endogenous Cu in the pig also were evaluated for their Cu bioefficacy. Freeze-dried (FD) porcine bile did not have any bioavailable Cu, whereas spray-dried porcine plasma contained Cu that was as available (99%) as that in CuSO4. In addition, when FD pork liver or FD porcine bile was added to the basal diet containing .5 mg of Cu/kg from CuSO4, Cu bioavailability in CuSO4 was reduced (P < .05) to 34% and 19%, respectively, of values obtained with CuSO4 alone. An additional experiment was conducted to estimate Cu bioefficacy in selected animal-source feed ingredients. Copper bioavailability in all-beef meat and bone meal, all-pork meat and bone meal, mixed-species meat and bone meal, high-bone meat and bone meal, poultry byproduct meal, and hog hair meal was 4, 53, 28, 8, 42, and 9%, respectively, relative to CuSO4. Feather meal did not provide any bioavailable Cu to chicks.
进行了三项雏鸡试验，以探究猪肝为何不能为雏鸡提供可生物利用铜的可能原因。高压灭菌、酸水解和蛋白酶消化分别将猪肝中的铜生物利用率提高（P <.01）至32%、46%和63%，而未加工猪肝中的铜生物利用率几乎为0%（相对于设定为100%的硫酸铜）。在含有1毫克/千克未加工猪肝铜的日粮中添加200毫克/千克乙二胺四乙酸（EDTA），也导致铜生物利用率提高（P <.07）至23%。还评估了代表猪体内不同内源性铜来源的组织的铜生物有效性。冻干猪胆汁不含任何可生物利用的铜，而喷雾干燥猪血浆所含的铜与硫酸铜中的铜一样具有生物有效性（99%）。此外，当将冻干猪肝或冻干猪胆汁添加到含有0.5毫克/千克硫酸铜的基础日粮中时，硫酸铜中的铜生物利用率分别降低（P <.05）至单独使用硫酸铜时所获值的34%和19%。还进行了一项额外试验，以估计选定动物源饲料原料中的铜生物有效性。相对于硫酸铜，全牛肉骨粉、全猪肉骨粉、混合物种肉骨粉、高骨肉骨粉、家禽副产品粉和猪毛粉中的铜生物利用率分别为4%、53%、28%、8%、42%和9%。羽毛粉不能为雏鸡提供任何可生物利用的铜。
